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Abstract Background In Xenopus retinogenesis, p27Xic1, a Xenopus cyclin dependent kinase inhibitor, functions as a cell fate determinant in both gliogenesis and neurogenesis in a context dependent manner. This activity is essential for co-ordination of determination and cell cycle regulation. However, very little is known about the mechanism regulating the context dependent choice between gliogenesis versus neurogenesis. Results We have identified NM23-X4, a NM23 family member, as a binding partner of p27Xic1. NM23-X4 is expressed at the periphery of the ciliary marginal zone of the Xenopus retina and the expression overlaps with p27Xic1 at the central side. Our in vivo functional analysis in Xenopus retina has shown that knockdown of NM23-X4 activates gliogenesis. Furthermore, co-overexpression of NM23-X4 with p27Xic1 results in the inhibition of p27Xic1-mediated gliogenesis, through direct interaction of NM23-X4 with the amino-terminal side of p27Xic1. This inhibitory effect on gliogenesis requires serine-150 and histidine-148, which correspond to the important residues for the kinase activities of NM23 family members. Conclusion This study demonstrates that NM23-X4 functions as an inhibitor of p27Xic1-mediated gliogenesis in Xenopus retina and suggests that this activity contributes to the proper spatio-temporal regulation of gliogenesis.

Currently, only a few reports exist on the cytokine release syndrome (CRS) as one of the severe immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs). Notably, it is very rare that grade 4 CRS related to ICI therapy overlaps with the drug-induced hypersensitivity syndrome (DiHS). A 46-year old woman with metastatic kidney cancer had grade 3 interstitial pneumonitis induced by four cycles of combination therapy of anti-programmed death-1 and anti-cytotoxic T lymphocyte-4 antibodies after right cytoreductive nephrectomy. Prophylactic administration of trimethoprim/sulfamethoxazole (TMP/SMX) was started concomitantly with prednisolone therapy to treat the interstitial pneumonitis. She developed hypotensive shock when reducing the dosage of prednisolone, and required intubation and ventilation using vasopressors at the intensive care unit. She subsequently exhibited prominent leukocytosis and an increased level of C-reactive protein, suggesting markedly increased cytokine levels. Interestingly, facial edema and erythema increased in association with pyrexia, leukocytosis, liver dysfunction, and renal failure, suggesting that she developed DiHS. She received hemodialysis three times, a plasma exchange, and anti-interleukin-6 therapy to treat severe renal dysfunction, a thrombotic thrombocytopenic purpura-suspected condition, and possible grade 4 CRS, respectively. Although these therapies did not elicit sufficient effects, high-dose administration of intravenous immunoglobulin was successful. With steroid mini-pulse therapy and the subsequent administration of prednisolone, she recovered successfully. To the best of our knowledge, this is the first report that ICIs and TMP/SMX can induce hypotensive shock accompanied with CRS and DiHS during immunosuppressive therapy for an irAE. Importantly, the prophylactic administration of TMP/SMX should be performed cautiously to avoid severe drug reactions such as CRS or DiHS. [ABSTRACT FROM AUTHOR]

• A total 21 quality indicators of palliative care were settled. • Symptom palliation and supporting decision-making process are two major domains. • Outcome measure could only be evaluated by bereaved family survey. Although recent attention to palliative care for patients with cardiovascular diseases has been increasing, there are no specific recommendations on detailed palliative care practices. We proceed on a discussion of the appropriateness and applicability of potential quality indicators for acute cardiovascular diseases according to our previous systematic review. We created a multidisciplinary panel of 20 team members and 7 external validation clinicians composed of clinical cardiologists, a nutritionist, a physiotherapist, a clinical psychologist, a critical and emergent care specialist, a catheterization specialist, a primary care specialist, a palliative care specialist, and nurses. After crafting potential indicators, we performed a Delphi rating, ranging from "1 = minimum" to "9 = maximum". The criterion for the adoption of candidate indicators was set at a total mean score of seven or more. Finally, we subcategorized these indicators into several domains by using exploratory factor analysis. Sixteen of the panel members (80%) were men (age, 49.5 ± 13.7 years old). Among the initial 32 indicators, consensus was initially reached on total 23 indicators (71.8%), which were then summarized into 21 measures by selecting relatively feasible time variations. The major domains were "symptom palliation" and "supporting the decision-making process". Factor analysis could not find optimal model. Narratively-developed seven sub-categories included "presence of palliative care team", "patient-family relationship", "multidisciplinary team approach", "policy of approaching patients", "symptom screening and management", "presence of ethical review board", "collecting and providing information for decision-maker", and "determination of treatment strategy and the sharing of the care team's decision". In this study we developed 21 quality indicators, which were categorized into 2 major domains and 7 sub-categories. These indicators might be useful for many healthcare providers in the initiation and enhancement of palliative care practices for acute cardiovascular diseases in Japan. [ABSTRACT FROM AUTHOR]

We designed and synthesized homochiral-peptide-based boron diketonate complexes. Co-administration of the two stereoisomers in cancer cells led to molecular assembly targeting both the plasma membrane and the lysosomes mediated via membrane-bonded enzymes. The dual-targeted-assembly generates a synergistic anticancer effect with amplified cancer spheroid toxicity and enhanced inhibition efficacy on cancer cell migration. [ABSTRACT FROM AUTHOR]

The Xenopus LIM homeodomain protein Xlim-1 is specifically expressed in the Spemann organizer region and assumed to play a role in the establishment of the body axis as a transcriptional activator. To further elucidate the mechanism underlying the regulation of its transcriptional activity, we focused on the region C-terminal to the homeodomain of Xlim-1 (CT239-403) and divided it into five regions, CCR1-5 (C-terminal conserved regions), based on similarity between Xlim-1 and its paralog, Xlim-5. The role of Xlim-1 CT239-403 in the Spemann organizer was analyzed by assaying the axis-forming ability of a series of CCR-mutated constructs in Xenopus embryos. We show that high doses of Xlim-1 constructs deleted of CCR1 or CCR2 initiate secondary axis formation in the absence of its coactivator Ldb1 (LIM-domain-binding protein 1), suggesting that CCR1 and CCR2 are involved in negative regulation of Xlim-1. In contrast, while Xlim-1 is capable of initiating secondary axis formation at low doses in the presence of Ldb1, deletion of CCR2 (aa 275-295) or substitution of five conserved tyrosines in CCR2 with alanines (CCR2-SYA) abolished the activity. In addition, UAS-GAL4 one-hybrid reporter assays in Xenopus showed that CCR2, but not CCR2-5YA, with its flanking regions (aa 261-315) functions as a transactivation domain when fused to the GAL4 DNA-binding domain. Finally, we show that none of the known transcriptional coactivators tested (CBP, SRC-1, and TIF2) interacts with the Xlim-1 transactivation domain (aa 261-315). Thus, Xlim-1 not only contains a unique tyrosine-rich activation domain but also contains a negative regulatory domain in CT239-403, suggesting a complex regulatory mechanism underlying the transcriptional activity of Xlim-1 in the organizer. [C] 2000 Academic Press Key Words: Xenopus laevis; Spemann organizer; axis formation; transcription factor; LIM homeodomain protein; LIM domain; negative regulation; transactivation; Xlim-1; Ldb1.

The homeobox genes Xlim-1 and goosecoid (gsc) are coexpressed in the Spemann organizer and later in the prechordal plate that acts as head organizer. Based on our previous finding that gsc is a possible target gene for Xlim-1, we studied the regulation of gsc transcription by Xlim-1 and other regulatory genes expressed at gastrula stages, by using gsc-luciferase reporter constructs injected into animal explants. A 492-bp upstream region of the gsc promoter responds to Xlim-1/3m, an activated form of Xlim-1, and to a combination of wild-type Xlim-1 and Ldb1, a LIM domain binding protein, supporting the view that gsc is a direct target of Xlim-1. Footprint and electrophoretic mobility shift assays with GST-homeodomain fusion proteins and embryo extracts overexpressing FLAG-tagged full-length proteins showed that the Xlim-1 homeodomain or Xlim-1/Ldb1 complex recognize several TAATXY core elements in the 492-bp upstream region, where XY is TA, TG, CA, or GG. Some of these elements are also bound by the ventral factor PV.1, whereas a TAATCT element did not bind Xlim-1 or PV.1 but did bind the anterior factors Otx2 and Gsc. These proteins modulate the activity of the gsc reporter in animal caps: Otx2 activates the reporter synergistically with Xlim-1 plus Ldbl, whereas Gsc and PV.1 strongly repress reporter activity. We show further, using animal cap assays, that the endogenous gsc gene was synergistically activated by Xlim-1, Ldb1, and Otx2 and that the endogenous otx2 gene was activated by Xlim-1/3m, and this activation was suppressed by the posterior factor Xbra. Based on these data, we propose a model for gene interactions in the specification of dorsoventral and anteroposterior differences in the mesoderm during gastrulation. [C] 2000 Academic Press Key Words: Xenopus; head organizer; homeobox gene; goosecoid promoter; Xlim-1; Ldb1; Otx2; Gsc; PV.1; Xvent-1; Xbra; LIM domain.

The precision and efficacy of photodynamic therapy (PDT) is essential for the treatment of brain tumors because the cancer cells are within or adjacent to the delicate nervous system. Taurine is an abundant amino acid in the brain that serves the central nervous system (CNS). A taurine-modified polypyridyl Ru-complex was shown to have optimized intracellular affinity in cancer cells through accumulation in lysosomes. Symmetrical modification of this Ru-complex by multiple taurine molecules enhanced the efficiency of molecular emission with boosted generation of reactive oxygen species. These characteristic features make the taurine-modified Ru-complex a potentially effective photosensitizer for PDT of target cancer cells, with outstanding efficacy in cancerous brain cells. [ABSTRACT FROM AUTHOR]

The article describes the case of a 49-year-old Japanese woman who received immune checkpoint inhibitor (ICI) pembrolizumab for oropharyngeal cancer, and reported a cold sensation, persistent erythema, and purple discoloration on her fingers, lower legs and feet. Topics covered include the medical history of the patient, the findings of the physical and laboratory tests which led to the diagnosis of chilblain lupus-like cutaneous reaction associated with systemic lupus erythematosus (SLE).

Pufferfish accumulate tetrodotoxin (TTX) mainly in the liver and ovary. This study aims at investigating the effect of TTX accumulation in the liver of cultured specimens of torafugu Takifugu rubripes on the hepatic gene expression by microarray analysis on Day 5 after the intramuscular administration of 0.25 mg TTX/kg body weight into the caudal muscle. TTX was detected in the liver, skin and ovary in the TTX-administered individuals. The total amount of TTX accumulated in the body was 67 ± 8% of the administered dose on Day 5. Compared with the buffer-administered control group, a total of 59 genes were significantly upregulated more than two-fold in the TTX-administered group, including those encoding chymotrypsin-like elastase family member 2A, transmembrane protein 168 and Rho GTP-activating protein 29. In contrast, a total of 427 genes were downregulated by TTX administration, including those encoding elongation factor G2, R-spondin-3, nuclear receptor activator 2 and fatty acyl-CoA hydrolase precursor. In conclusion, our results demonstrate that the intramuscular administration of TTX changes the expression of hepatic genes involved in various signaling pathways. [ABSTRACT FROM AUTHOR]

Background: In Xenopus retinogenesis, p27Xic1, a Xenopus cyclin dependent kinase inhibitor, functions as a cell fate determinant in both gliogenesis and neurogenesis in a context dependent manner. This activity is essential for co-ordination of determination and cell cycle regulation. However, very little is known about the mechanism regulating the context dependent choice between gliogenesis versus neurogenesis. Results: We have identified NM23-X4, a NM23 family member, as a binding partner of p27Xic1. NM23-X4 is expressed at the periphery of the ciliary marginal zone of the Xenopus retina and the expression overlaps with p27Xic1 at the central side. Our in vivo functional analysis in Xenopus retina has shown that knockdown of NM23-X4 activates gliogenesis. Furthermore, cooverexpression of NM23-X4 with p27Xic1 results in the inhibition of p27Xic1-mediated gliogenesis, through direct interaction of NM23-X4 with the amino-terminal side of p27Xic1. This inhibitory effect on gliogenesis requires serine-150 and histidine-148, which correspond to the important residues for the kinase activities of NM23 family members. Conclusion: This study demonstrates that NM23-X4 functions as an inhibitor of p27Xic1- mediated gliogenesis in Xenopus retina and suggests that this activity contributes to the proper spatio-temporal regulation of gliogenesis. [ABSTRACT FROM AUTHOR]

Signals by cytokines of the transforming growth factor-β (TGF-β) superfamily are negatively regulated by inhibitory Smads (I-Smads). Smad7 inhibits signaling by both TGF-β and bone morphogenetic proteins (BMPs), whereas Smad6 inhibits TGF-β signals less effectively. I-Smads have amino-terminal N domains and carboxylterminal Mad homology 2 (MH2) domains. The N domains are essential for specific inhibition of TGF-β signaling by Smad7, whereas the MH2 domains of I-Smads are involved in the inhibition of TGF-β superfamily signals through interaction with type I receptors. Here, we have identified four basic amino acid residues (Lys-312, Lys-316, Lys-401, and Arg-409) in the basic surface of the Smad7 MH2 domain that play important roles in interaction with type I receptors. Mutations of the four basic amino acid residues to acidic residues (K312E, K316E, K401E, and R409E) abolished the interaction of Smad7 with TGF-β type I receptors, inhibition of Smad2 phosphorylation and transcriptional responses induced by TGF-β, and induction of target genes of endogenous activin/Nodal signals in Xenopus early embryos. The K401E and R409E mutants of Smad7 were also unable to interact with BMP type I receptors (BMPR-I), repress the Smad5 phosphorylation and transcription induced by BMP, and effectively inhibit endogenous BMP signals in Xenopus early embryos. However, the K312E and K316E mutants were able to interact with BMPR-I and retained the ability to inhibit BMP signaling. Thus, the MH2 domain of Smad7 plays important roles in specific inhibition of TGF-β superfamily signals through differential interaction with type I receptors. [ABSTRACT FROM AUTHOR]

Presents a study that isolated a Xenopus ortholog (XRnf12) of the RING finger protein Rnf12/RLIM and explored its functional interactions with Xlim-1 and Ldb1. Role of Spemann organizer in body axis determination in vertebrates; Details on embryo manipulations, preparation of synthetic mRNA and RNA injections; Isolation and characterization of XRnf12.

Correction for ‘Enzyme-mediated dual-targeted-assembly realizes a synergistic anticancer effect’ by Dingze Mang et al., Chem. Commun., 2019, 55, 6126–6129. [ABSTRACT FROM AUTHOR]

Summary: Aim: Dexmedetomidine is a highly specific and selective α-2 adrenergic agonist that is now widely used in the intensive care setting. Many intensive care unit (ICU) patients are at risk of respiratory or cardiac arrest. This study was conducted to determine whether dexmedetomidine exhibits a cardioprotective effect on global ischaemia and subsequent myocardial infarction. Methods: Isolated rat hearts were subjected to 30min of global ischaemia followed by 120min reperfusion, with administration of 0, 1 and 10nM dexmedetomidine during the pre-ischaemic period (n =7 each group). Secondly, 1μM yohimbine, an α-2 antagonist, was given during the pre-ischaemic period, alone or in combination with 10nM dexmedetomidine (n =7 each group). Results: Dexmedetomidine administration reduced coronary flow significantly (103.6±4.7%, 77.9±3.7, 63.7±6.1%, of the baseline values for 0, 1 and 10nM dexmedetomidine, respectively), and yohimbine administration reversed this effect (88.0±2.2%). Dexmedetomidine improved the infarct size at each concentration (45.3±3.6, 30.2±3.3, and 21.2±2.3% of the total left ventricular mass for 0, 1, and 10nM dexmedetomidine, respectively), which was also reversed by yohimbine (43.6±1.4%). Conclusion: Dexmedetomidine exhibited a cardioprotective effect on global ischaemia in the isolated rat heart model, which was mediated by α-2 adrenergic stimulation. [Copyright &y& Elsevier]

Summary: Intracellular vesicular transport is important for photoreceptor function and maintenance. However, the mechanism underlying photoreceptor degeneration in response to vesicular transport defects is unknown. Here, we report that photoreceptors undergo apoptosis in a zebrafish β-soluble N-ethylmaleimide-sensitive factor attachment protein (β-SNAP) mutant. β-SNAP cooperates with N-ethylmaleimide-sensitive factor to recycle the SNAP receptor (SNARE), a key component of the membrane fusion machinery, by disassembling the cis-SNARE complex generated in the vesicular fusion process. We found that photoreceptor apoptosis in the β-SNAP mutant was dependent on the BH3-only protein BNip1. BNip1 functions as a component of the syntaxin-18 SNARE complex and regulates retrograde transport from the Golgi to the endoplasmic reticulum. Failure to disassemble the syntaxin-18 cis-SNARE complex caused BNip1-dependent apoptosis. These data suggest that the syntaxin-18 cis-SNARE complex functions as an alarm factor that monitors vesicular fusion competence and that BNip1 transforms vesicular fusion defects into photoreceptor apoptosis. [Copyright &y& Elsevier]

In vertebrate lens, lens epithelial cells cover the anterior half of the lens fiber core. Lens epithelial cells proliferate, move posteriorly and start to differentiate into lens fiber cells at the lens equator. Although FGF signaling promotes this equatorial commencement of lens fiber differentiation, the underlying mechanism is not fully understood. Here, we show that lens epithelial cells abnormally enter lens fiber differentiation without passing through the equator in zebrafish vps45 mutants. VPS45 belongs to the Sec1/Munc18-like protein family and promotes endosome trafficking, which differentially modulates signal transduction. Ectopic lens fiber differentiation in vps45 mutants does not depend on FGF, but is mediated through activation of TGFβ signaling and inhibition of canonical Wnt signaling. Thus, VPS45 normally suppresses lens fiber differentiation in the anterior region of lens epithelium by modulating TGFβ and canonical Wnt signaling pathways. These data indicate a novel role of endosome trafficking to ensure equator-dependent commencement of lens fiber differentiation., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2018. Published by The Company of Biologists Ltd.)

In vertebrates, lens epithelial cells cover the anterior half of the lens fiber core. During development, lens epithelial cells proliferate, move posteriorly and differentiate into lens fiber cells after passing through the equator. To elucidate the mechanisms underlying lens epithelial cell movement, we conducted time-lapse imaging of zebrafish lens epithelium. Lens epithelial cells do not intermingle but maintain their relative positions during development. Cell division induces epithelial rearrangement, which subsequently promotes cell movement towards the equator. These data suggest that cell division is the major driving force for cell movement. In zebrafish, E-cadherin is expressed in lens epithelium, whereas N-cadherin is required for lens fiber growth. E-cadherin reduced lens epithelial cell movement, whereas N-cadherin enhanced it. Laser ablation experiments revealed that lens epithelium is governed by pulling tension, which is modulated by these cadherins. Thus, cell division and cadherin-mediated adhesion regulate lens epithelial cell movement via modulation of epithelial tension., (© 2017. Published by The Company of Biologists Ltd.)

Cell proliferation is a key regulator of tissue morphogenesis. We examined cell proliferation and cell division in zebrafish lens epithelium by visualizing cell-cycle phases and nuclear positions, using fluorescent-labeled geminin and histone proteins. Proliferation was low in the anterior region of lens epithelium and higher in the marginal zone anterior to the equator, suggesting that the proliferation zone, called the germinative zone, is formed in zebrafish lens. Interestingly, cell-division orientation was biased longitudinally in the anterior region, shifted from longitudinal to circumferential along the anterior-posterior axis of lens sphere, and was biased circumferentially in the peripheral region. These data suggest that cell-division orientation is spatially regulated in zebrafish lens epithelium. The Hertwig rule indicates that cells tend to divide along their long axes. Orientation of long axes and cell division were biased similarly in zebrafish lens epithelium, suggesting that cell geometry correlates with cell-division orientation. A cell adhesion molecule, E-cadherin, is expressed in lens epithelium. In a zebrafish e-cadherin mutant, the long axes and cell-division orientation were shifted more longitudinally. These data suggest that E-cadherin is required for the spatial pattern of cell geometry and cell-division orientation in zebrafish lens epithelium., (© 2014. Published by The Company of Biologists Ltd.)

In this study, we aimed to compare the effects of low- and high-quality cardiopulmonary resuscitation (CPR) on cardioprotection by induced hypothermia (IH) at 34 °C and examine whether extracellular signal-regulated kinase or endothelial nitric oxide synthase mediates this cardioprotection. Left ventricle infarct sizes were evaluated in six groups of rat hearts (n = 6) following Langendorff perfusion and triphenyltetrazolium chloride staining. Controls underwent 30 min of global ischemia at 37 °C, followed by 10 min of simulated low- or high-quality CPR reperfusion and 90 min of reperfusion at 75 mmHg. The IH groups underwent IH at 34 °C during reperfusion. The U0126 group received U0126 (60 μM)-an extracellular signal-regulated kinase inhibitor-during reperfusion at 34 °C. The L-NIO (N-(1-iminoethyl)-L-ornithine dihydrochloride) group received L-NIO (2 μM)-an endothelial nitric oxide synthase inhibitor-5 min before global ischemia at 37 °C to the end of reperfusion at 34 °C. Infarct size did not significantly differ between the control and IH groups receiving low-quality CPR. However, IH with high-quality CPR reduced the infarct size from 47.2% ± 10.2% to 26.0% ± 9.4% (P = 0.005). U0126 reversed the IH-induced cardioprotection (45.9% ± 9.4%, P = 0.010), whereas L-NIO had no significant effect. Cardiopulmonary resuscitation quality affects IH-induced cardioprotection. Extracellular signal-regulated kinase may mediate IH-induced cardioprotection.

We experienced a case of unexpected difficult nasal intubation due to lingual tonsil hyperplasia. A 43-year-old man was scheduled for pharyngoplasty because of sleep apnea syndrome. After induction of general anesthesia, Macintosh laryngoscopy failed to expose his glottis by two experienced anesthesiologists. We also found that the view of his larynx by fiberoptic bronchoscope (FOB) was poor, and nasal intubation guided by FOB was difficult. Finally, we made an oral intubation with Macintosh laryngoscopy under a gum elastic bougie guide. Ventilation and oxygenation were maintained throughout the procedure. A FOB guided intubation under general anesthesia is often difficult, because identification of glottis is interfered by deviated pharyngeal tissue and epiglottis, which are affected by the use of muscle relaxants. At present, a selective relaxant binding agent, sugammadex, is available in anesthesia, to reverse the effect of non-depolarizing muscle relaxant and to restore spontaneous breathing in this situation.

There is a general consensus that patients who attempt suicide require intervention for psychological as well as physical problems. However, among the institutions accepting patients who attempt suicide, there are few institutions employing a full-time psychiatrist in the emergency department. Therefore, it is difficult to conduct a suicide re-attempt risk evaluation in the presence of a psychiatric specialist. We developed a suicide re-attempt risk evaluation scale to be used by non-professional staff. We asked the medical staff that cared for patients who had attempted suicide to record all the evaluation items in the patient's medical record. We utilized an interview method and highlighted the types of answers that needed special attention. When there were two or more answers that needed special attention, we defined the patient as high risk. The number of days of hospitalization did not change as a result of the use of the suicide re-attempt risk estimate scale; however, the quantity of medical records addressing suicide intention and the rate of psychiatric intervention significantly increased. It is unclear whether this score directly led to the prevention of repeat suicide attempts. However, it is notable that use of the scale has led to a change in the behavior of medical staff by mandating a fixed-format risk evaluation.